lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <Pine.LNX.4.64.0708141517340.32624@schroedinger.engr.sgi.com>
Date:	Tue, 14 Aug 2007 15:20:28 -0700 (PDT)
From:	Christoph Lameter <clameter@....com>
To:	Andi Kleen <andi@...stfloor.org>
cc:	linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: Re: [RFC 4/9] Atomic reclaim: Save irq flags in vmscan.c

On Wed, 15 Aug 2007, Andi Kleen wrote:

> > > The interrupt handler shouldn't touch zone_flag. If it wants
> > > to it would need to be converted to a local_t and incremented/decremented
> > > (should be about the same cost at least on architectures with sane
> > > local_t implementation) 
> > 
> > That would mean we need to fork the code for reclaim?
> 
> Not with the local_t increment.

Ok I have a vague idea on how this could but its likely that the 
changes make things worse rather than better. Additional reference to a 
new cacheline (per cpu but still), preempt disable. Lots of code at all
call sites. Interrupt enable/disable is quite efficient in recent 
processors.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ